Dust from a giant asteroid crash caused an ancient ice age
About 466 million years ago, long before the age of the dinosaurs, the Earth froze. The seas began to ice over at the Earth’s poles, and new species evolved with the new temperatures. The cause of this ice age was a mystery, until now: a new study argues that the ice age was caused by global cooling, triggered by extra dust in the atmosphere from a giant asteroid collision in outer space.
Paleontology News — ScienceDaily